Mulberry fruits are juicy, aromatic and delicious, but rarely found in shops, so well worth growing. The large, long-lived trees also make an architectural feature thanks to their spreading habit and crooked, gnarled shape.
The fruits of the black mulberry (Morus nigra) have a unique and delicious, sweet tangy flavour – an irresistible late-summer treat eaten fresh from the tree or made into desserts and jams.
Black mulberries form large, handsome trees with wide-spreading branches, attractive heart-shaped foliage and red/black berries. These long-lived trees often form characterful, gnarly shapes and can eventually reach 9m (30ft) tall and wide, so are best suited to large gardens, making a beautiful central feature in a lawn. To keep them more compact, you can train them as espaliers against a warm, sunny wall, or prune into a smaller bush form.
There are some compact hybrids that will grow around 1.5m (5ft) when container grown.
Mulberries are easy to plant, in the ground or in containers. As they are slow growing, they can be kept in a large container for many years.
Mulberry trees are self-fertile, so you only need one to produce a good crop. However, you may have to wait eight or so years for your first black mulberry fruits, although more compact varieties tend to fruit more quickly. Once well established, mulberries crop abundantly through August and September.
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There are several species of mulberry, but it is the black mulberry (Morus nigra) that has the best flavoured fruits. However, black mulberries trees eventually grow very large, up to 9m (30ft) tall and wide, so need a lot of space.
Fortunately, there is compact variety ‘Charlotte Russe’ which will reach only 1.5m (5ft) tall if container grown. It will fruit in its first year. It won Plant of the Year at the RHS Chelsea Flower Show in 2017.
What and where to buy
Black mulberry trees are mainly available from fruit nurseries, although you may find them in larger garden centres. Specialist fruit tree suppliers may offer a choice of several smaller varieties, more suitable for average or smaller gardens.
Mulberry trees are usually sold in containers, in a range of sizes. Bare-root trees (without soil around the roots) may also be available during the dormant season, from autumn to spring, and can often be pre-ordered. Bare-root trees are usually a cheaper option.
If you buy a tree that has already been part-trained into a standard form (lollipop shaped) or half-standard (with a shorter trunk), it will make a well-formed tree more quickly.
Mulberries like deep, moisture-retentive but well-drained soil that has been enriched with well-rotted manure or garden compost.
Choose a sunny, sheltered planting spot, where the tree will have plenty of room to develop its wide shape – black mulberries can eventually reach up to 9m (30ft) across.
Mulberry trees look great as a centrepiece in a lawn, with plenty of space around them so you can enjoy their handsome, gnarled appearance to the full. They can also be planted against a warm sunny wall, especially in colder locations.
Both bare-root and container-grown trees are best planted while dormant, from autumn to spring, but should settle in best when planted in spring as the soil is warming up. Insert a sturdy stake to support the young tree and prevent windrock and ensure good root development.
Planting in a container
Compact mulberries are well-suited planting large containers, ideally 50cm (20in) wide, filled with a soil-based compost, such as John Innes No. 3.
They should grow happily for 10–15 years, if watered carefully in summer and repotted into larger containers as they grow.
Once established, mulberry trees need very little maintenance – they are hardy, robust, slow-growing trees that can live for hundreds of years. They often make wide, lop-sided, gnarly specimens over time, but that is all part of their charm.
Keep newly planted trees well watered during the growing season for its first few years. Established trees shouldn’t need additional watering, except during droughts or in very free-draining soil.
Mulberry trees in containers need regular watering throughout the growing season, but especially in summer. See our guide to growing fruit in containers.
To boost cropping, feed in early spring with a high potassium general fertiliser, such as Vitax Q4 or fish, blood and bone. Scatter one handful per square metre/yard around trees growing in bare soil, and one and a half around those in grass.
After feeding in spring, apply a mulch of organic matter, such as well-rotted manure or garden compost, around the base of the tree, but not right up to the trunk. This will help to hold moisture in the soil and deter weeds.
Extra care for plants in containers
Before growth re-starts in spring, re-pot young trees into a slightly larger container each year as they grow. Use fresh soil-based compost.
Pruning and Training
Mulberries are usually grown as free-standing trees, trained as standard or half-standard trees, with a bare trunk topped with a wide canopy of branches. Any pruning is best done while they are dormant, ideally in the autumn after leaf fall, as they bleed a lot of sap if cut in after mid-winter.
If you don’t have room for a large tree, you can train a mulberry tree flat against a sunny wall or fence, as an espalier, with several tiers of horizontal branches. Alternatively, grow a compact cultivar.
- Bush (tree on a short trunk) – in early winter, prune back the main upright shoot (leader) of a young tree to 70–90cm (28–32in) tall, cutting just above some strong side-shoots. Allow these to develop into a framework of eight to ten branches, as for bush apples. After that, generally only minimal pruning is required. If needed, remove any dead, damaged, crossing or overcrowded branches. If you wish to keep a neat shape, you can also remove wayward branches or any that sprout from the trunk below the main canopy.
- Standard or half-standard trees – they are pruned in the same way as bush trees, but with a taller clear trunk than bush trees – 1.2–1.5m (4–5ft) for half-standards and 1.8–2.1m (6–7ft) for standards.
- Espalier trees –mulberries can be trained flat against a sunny, sheltered wall. Start with a young tree preferably one- to two-year-old. Prune and traine as for apple espalier. When summer pruning, prune more lightly than you would do for apples. Shorten the new side-shoots that sprout from branches to three or four leaves to produce short fruiting spurs. Do this in late summer, just as growth is slowing down.
In general, established mulberry trees need very little pruning and can be left to form a wide-spreading canopy, often developing a gnarly, crooked appearance as they age.
Mulberry fruits resemble large blackberries, turning from red to glossy black when ripe – wait until they are soft and juicy with a deliciously sweet, tangy flavour. The main harvesting season is between August and September.
Pick fruits on low branches individually when ripe, wearing gloves if you prefer, to avoid staining your hands.
The easiest way to gather fruit from large trees is by shaking the branches over a sheet spread on the ground.
Black mulberry trees are slow to start fruiting, often taking around eight years, although some smaller varieties may bear fruit in only half that time.
Mulberry trees are generally healthy and robust once settled in, but don’t expect fruit straight away – you’ll need to wait several years for your first crop. Birds will help themselves to the berries too, but will hopefully leave plenty, hidden among the leaves, for you to enjoy.
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